This application is the U.S. national phase of International Application No. PCT/IT2005/000597 filed Oct. 12, 2005, the disclosure of which is incorporated herein by reference in its entirety. The International Application was published in English on Apr. 19, 2007 as WO 2007/043072A1 under PCT Article 21(2).
The technology disclosed herein discloses a steering device particularly usable, but not exclusively, for motor vehicles and the following description has been made referring to this field of application only with the purpose to make the description easier.
However, the device is usable also for trolley vehicles, farm machinery, public works vehicles, motor boats, amphibious vehicles, and the like or for any vehicle allowing a movement even if not rectilinear.
As it is well known, starting from the first motor vehicles, the steering control has always been transmitted from a steering device, usually known as a “steering wheel” fixed on a central hub and connected, by means of a steering column, to steering mechanisms controlling the directioning position of the front wheels. Over the years, the steering wheels have been modified and improved in design, ergonomics, adjustment etc.
Nowadays steering wheels exist which are adjustable in height and inclination, made of different materials, stronger and, at the same time, of lighter weight, steering wheels that are able to absorb shocks, thanks to modification to the steering column, or more simply, equipped with instantaneously inflatable cushions (called airbags) to protect the driver in case of collision.
The shape of the steering wheels has changed, in some cases, as for example in “Formula One”, in which steering wheels of semicircular shaped and extractable from the driver have been used, to satisfy more restrictive space needs, during the driving and upon getting in and out of the vehicle.
The way in which the steering is controlled has not changed. The steering control is applied by the driver of the vehicle to the steering wheel; safety rules and highway code require the driver to hold the steering wheel with both hands, while driving, in order to have a better control of the vehicle.
However, in particular driving conditions, for example in reverse motion, or in U-turn, it is uncomfortable to keep both hands onto the steering wheel; during reverse motion, the position of the driver is unnatural in comparison with the normal driving position, the driver being partially or totally turned backwards, thereby he tends to detach one hand from the steering wheel.
Moreover in case of elbow bends, sudden swerving, steering corrections, etc. it is also difficult to timely steer, the steering wheel having an intrinsic resistance against the rotation.
This last inconvenience is more evident under driving conditions already naturally extreme like in rallies, road races, track races or the like.
The need of avoiding frequently detaching the hands from the steering wheel, in event of bends, U-turns and reverse motion, causes the driver to accompany hands on the steering wheel, the rotation of the steering wheel as far as possible, leading to a torsion of the arms in the direction of the steering. This fact results in a continuous stress on the muscles of the arms increasing in time and in proportion to non rectilinear paths. In JP 11 342849 A to Honda Motor Co. Ltd. the arm, opposite to the direction of rotation, suffers for the same continuous stress, during a rotation of the steering wheel.
Moreover, the aforementioned stresses are a not negligible problem for drivers unskilled or poorly inclined to the driving.
Under extreme driving conditions, as rallies, road races, or track races, the crosswire acceleration acting during bends amplifies even more the stresses acting on the arms and on the shoulders making it necessary a high physical effort to drive the vehicle.
The purpose of the technology disclosed herein is to provide a steering device having structural and functional features to overcome the above described drawbacks.
A particular purpose of the technology disclosed herein is thus to guarantee greater driving safety, to reduce the effort needed for the steering control and to reduce the stress on the arms and the shoulders during the steering.
These purposes are achieved by means a steering device comprising a support structure fixed on a steering column by means of a central hub and rotatable with the steering column to operate control mechanisms for the direction of the front wheels, characterised by comprising at least two handgrips, at least one of which being mobile, connected to the support structure, said at least one mobile handgrip being rotatable around an axis substantially orthogonal to the lying and rotating plane of the support structure so as to manually impart a rotating motion, around the steering column axis, to said support structure.
According to a preferred embodiment of the technology disclosed herein, the device comprises two mobile handgrips, fastened to said support structure in symmetrical positions with respect to the mid-plane of the support structure, said handgrips being shaped for the normal grip by the two hands of the driver.